Assuming you’ve been keeping up with the series, you should be saying to yourself “Hey, maybe this fasting thing would be a cool thing to try out, and it might even make me healthier/live longer/lean out/lose weight/etc.,” which is a sufficiently extensive list of benefits, don’t you think? I could probably go on theorizing and speculating about all the reasons why you should consider intermittent fasting, but I’d rather move on to the implementation. Thinking about fasting, reading about fasting, and reciting the benefits of fasting are all pointless if you don’t know how to go about doing it.

First, let’s go over the different variations of fasting. I’ll give a quick rundown. Each involves not eating for a period of time, unsurprisingly.

A couple other rules that apply to all the given methods:

Sleeping hours (provided you don’t sleep-eat) count as fasting hours.

Eat well regardless. While some fasting plans tout their adherents’ ability to eat crappy food and still lose weight, I’m not interested in fasting solely as a weight loss method.

Leangains

A daily 16 hour fast (Martin sometimes recommends 14 for women, who just seem to do better on shorter fasts) during which you eat nothing. Coffee, tea, and other non-caloric fluids are fine.

A daily 8 hour (or 10 for women) eating window.

Three days of weight training, ideally performed at the tail end of the fasting period. To improve performance and muscle protein synthesis, you have the option of consuming 10 grams of branched chain amino acids 10 minutes before the workout.

Most people begin their fast after dinner (say, 9 PM), workout in the afternoon (at around 12 PM), and break their fast immediately post-workout (at around 1 PM), but you can use any schedule you prefer.

Because it’s geared toward people interested in losing fat and putting on muscle and strength, Leangains presupposes that you will also be lifting heavy things several times a week, usually in the fasted state. Therefore, Leangains is best-suited for people who will be training on a regular basis. In fact, it’s probably the most meticulously-designed IF program.

People with steady schedules will have more success than people with erratic schedules. A huge part of Leangains is the hormonal entrainment induced by regular feeding times. Once you get locked into your routine, your hunger hormones will adapt to the schedule, and the fasting should get easier, or even effortless.

Eat Stop Eat

Start your fast in the morning, at lunch, or at dinner. It doesn’t matter as long as you don’t eat for 24 hours.

Break your fast with a “normal-sized meal.” Don’t try to make up for the lost calories by feasting.

Exercise regularly.

Who should try it?

People interesting in fasting for the therapeutic benefits (cancer protection, autophagy, life extension, etc.) would probably get a lot out of this method, as opposed to people interested in the body composition benefits.

Going a full 24 hours without food is a much tougher slog than going for 16 hours. In my experience, going lower-carb and higher-fat makes longer fasts easier, so I’d have to say a low-carb Primal eater would do better than most.

The Warrior Diet

Ori Hofmekler’s plan is based on the feast-and-fast concept:

Eat one meal a day, at night, and make it a big one. A real feast. You have three or four hours to eat until full. So it’s basically 20/4 hours.

You can occasionally snack on low-calorie raw fruit and vegetables during the day, but try to limit protein as much as possible until the feast.

Exercise during the day, in a fasted state.

Who should try it?

People who have trouble sticking to a stricter fast will do better on the Warrior Diet, as it allows light eating during the time leading up to the feast, but I wonder if you’d be squandering some of the benefits by eating.

Alternate Day Fasting

Researchers often use this method in lab studies:

Eat normally one day (last meal at, say, 9 PM Monday).

Don’t eat the next day.

Resume eating the day after that (at, say, 9 AM Wednesday).

It works out to a 36-ish hour fast, although there’s plenty of wiggle room. You could eat at 10 PM Monday and break the fast at 6 AM Wednesday for a “mere” 32 hour fast.

Who should try it?

People who have no trouble going to bed hungry. With Leangains, Eat Stop Eat, and the Warrior Diet methods, you can always manage to get to bed with a full belly; with ADF, you will be going to bed on an empty stomach several times a week. That can be tough.

That said, the therapeutic benefits to serious conditions will most likely really be pronounced with this way of fasting. The casual 20-something Primal eater who lifts heavy things and enjoys going out with friends? Probably not ideal. The older Primal eater interested in generating some autophagy and maybe staving off neurodegeneration? It might just work out. And while I’m not able to tell a cancer patient undergoing chemotherapy what to do, I’d guess that the longer fasts will be more beneficial in that regard, too.

But my personal favorite way of implementing fasting?

Eat WHEN – When Hunger Ensues Naturally

I’m not going to put any bullet points here, because none are required. Instead, I’ll give a few scenarios:

I wake up bright and early on a Saturday morning. It’s about 65 degrees, the sun’s out, Buddha’s walking around with the leash in his mouth, and Red Rock Canyon is kinda calling my name. I’ve got my coffee already and I’m actually not all that hungry from dinner. You know what? I’ll go on that hike, skip breakfast, and really work up an appetite for lunch. Or not. If I’m hungry afterwards, I’ll eat. It’s a fast, but not really.

I hit the gym, put in a light workout, then swing by the beach for some sand sprints. I’m toast by the end and have to stagger back to my car, but I’m not hungry. Even when I get home and smell the grilled salmon, I have no desire for it. I might eat later that night, but only if my appetite returns. I’m fasting post-workout only because it doesn’t occur to me to eat, not because I’m following a plan.

I’m away on business, stuck on a layover that’s turned into a delay that’s turned into an overnighter. The only food available is a Kudos candy bar – I mean, healthy granola bar (they seriously still make these?) from the mini fridge, a greasy pizza joint on the corner across the street from the hotel, a Chinese takeout place next to the pizza joint, and a slew of fast food restaurants some ways down the road. It’s late, I’m tired, I had a Big Ass Salad before I left for LAX… you know what? I’m just going to skip the “meal.” I’ll figure out something at the airport in the morning (20 hour fast) or once I land (24 hour fast). And I’ll be okay either way.

That’s eating When Hunger Ensues Naturally.

This is the most natural, most effortless way of “fasting,” at least for me, because it allows a person to eat intuitively. Although most people will eventually acclimate to more regimented fasting schedules, and many may even need and thrive with that structure, I prefer a more fractal, loose, random pattern of “missing” (in quotations because I don’t feel like I’m missing anything, and that’s the whole point!) meals. I have no data on whether it’s as effective or more effective than the more popular methods, but I do know that I’ll often fast for 16 hours and eat for eight, or skip an entire day of eating, or sometimes (but very, very rarely) even approach a full 30 hours, and it seems likely that this random pattern of eating characterized the eating “schedules” of our ancestors.

In short, we’re all doing the same thing, chasing the same goals. We’re all skipping meals, reducing calories, staying active, and all the while we’re doing this without feeling miserable and restricted. It just so happens that because we’re efficient Primal fat-burning beasts, switching over to burning our own body fat reserves for energy during a fast is a natural, seamless transition. We often don’t even notice it. There’s no effort involved.

That’s the key: lack of stress. If any or all of these fasting methods stress you out, make you irritable, kill your performance, make you feel restricted, or reduce your ability to enjoy life, and these feelings persist beyond the first five fasts you attempt (when some adaptation difficulties are totally expected), you shouldn’t employ them. You should shelve fasting for a while and come back to it later, or never. It’s not a “requirement” or anything. It’s just a tool you can wield if your situation warrants it. In fact, this is the perfect opportunity to conduct an informal experiment of one. Try Leangains for a week or two, then throw in a full 24 hour fast once or twice a week for a bit, then try the WHEN method. Compare and contrast. How did you feel? How did you perform at work, at home, and in the gym? Take some waist measurements perhaps, or analyze your favorite barometer of body composition to see how the different fasting methods worked – or didn’t work – for you.

Now, I’d like to hear from you. What’s your favorite fasting method? Do you have one, or you just kinda go with the flow? Be sure to review the previous installments below and if you have any questions about any of the stuff I’ve covered in this series, leave them in the comment section and I’ll try to get them answered for you next week. Thanks for reading!

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You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

Going with the flow and applying WHEN has me satisfied so that I doubt I’ll try another method anytime soon. Thanks for the info! Great series and I love the discussions that ensue.

Same here. In the morning, I don’t eat until I have a appetite. Sometimes that is when I get up. On those mornings, I immediately have something like bacon and eggs, and maybe a little fruit. Then I may have only a snack e.g. some nuts between then and dinner. Or I might have a light salad for lunch. Other days I am not hungry until 11 or even noon.

Same here. I do 16 hours when I feel like it. Not regularly though. Longer ones are not for me. And definitely no high sugar 50% of calories during one sitting AKA Leangains. Tried it and it brought back my cravings and expanded my belly – sixpack or not, a big belly is not a pleasant sight

HI, I tried to post but not sure if it worked. Have been IF for about two weeks. 14-16 hour fast each day. Wondering if it is okay to do if trying to get pregnant. Worried it might reduce my changes of conceiving??

hi. i am a midwifery student and from what my teachers have told me it is very good to do a fast a few weeks before conceiving, then the weeks prior to conception its best to eat as much nourishing things as possible. once pregnant i don’t believe even a 12 hour fast would be a good idea.

Mark Sisson is just talking out of his brain-dead ass. Fasting makes people weaker, it makes it difficult to think clearly, it makes people vulnerable to infectious diseases, and people at work will subject you to well-deserved ridicule. Sisson and his brainless, luddite, anti-religious, racist followers need some good, hard skull crackings in reality.

You do realize people fast for religious reasons all the time right? Easter just passed and I fasted for the week. I ate occasionally, but to be honest I still had energy and though I had cravings, they eventually went away. PS: You need a hug. Not sure why you carry so much hate, but its not serving you. Life’s too short to spend it so angry

If it didn’t work and you were really doing it right, I grow more concerned for your hormones and health. This works on almost all my patients except those with thyroid issues or other more severe problems. You may need to get checked.

Dr Jason wrote on August 3rd, 2012

No, you’re upset because you’ve screwed up your endogenous endorphin production via some type of mind-altering chemical abuse. The road back is long and even more depressing. Good luck.

I have been complete fasting for 3 days now . I started at 120.5 kilos now 116 kilos neat. I have been drinking lots of water and have had a cup of coffe or tea each day no sugar or sweetner. I dont feel hungry any more ,i have lost the bloated feel i had. Today i have plenty of energy and i am in a fairly high state of ketosis ( checked urine by keto strips). I did get a bit of a headace after the first 24 hrs as my body (liver) switched to burning fat instead of sugar. I will keep up my fast until the weight loss tapers off to less than 1/2 a kilo per day then i will slowly start to eat small amounts of pure protein (steak, bacon,eggs) . I am hoping to lose around 10 kilos in 10 days then i can slowly add vegeis etc and start to exerecise more. I should be able to ride my push bike without flattening the tyres by then. I will let you know how i go. By the way I started the fast first off my own acoord. I just felt it was something i needed to do. I then decide to check the web to see if there was any reason i should not be fasting, thats when i found this article.

Now on my 4th morning weighing in at 115.2 kg thats 5 kilos lighter in 4 days . Im feeling good not at all hungry, dont think i could run 5ks but im up to working around the yard and doing most of my usual routine. I have a doctors apointment this evening so i will have my blood sugar levels checked. I had full bloods taken the day before i started to fast including liver function etc. It will be interesting to see what changes if any occur when i finish fasting. I am seriously thinking of staying on the fast for around 30 days this will hopefully get my weight below 90 kg and put an end to my fatty liver.

I have been doing essentially Eat Stop Eat (I call it starving Thursdays) for a couple of months now. I have to say that as long as my last meal before the fast and my first meal after the fast are mostly protein and fat, I hardly notice the circa 26 hour fast. And this form of fasting has really accelerated my excess body weight loss. (24 lbs in less than 3 months).

It depends on your current level of strength. If you’re new to powerlifting, you can pretty much gain strength doing anything. Just the simple act of lifting a few heavy weights will make you stronger.

If you’re an advanced lifter (i.e., someone who can squat/dead 400+ and bench 250+), you’ll probably find it hard to make strength gains when fasting.

I don’t have any hard data on this, but I know several advanced lifters whose numbers plateaued or even dropped when implementing a fasting regimen. You pretty much have to eat lots of food to make strength gains when you get to that point.

Good point. How about the goal being: Lean, getting stronger, and being healthy?
My fasts affect the workouts. The performance drops. Food is energy. Energy=good workout results. Fasts = subpar workouts for me. So, I eat a little prior to and after workouts, which keeps me going strong and shortens wod rcovery.

David wrote on April 17th, 2012

“Isn’t the goal to be lean and healthy?”

Really? What is “the” goal? Your goal is whatever the hell your goal is, not whatever you hope is the consensus goal.

John wrote on April 17th, 2012

The goal for Brian seems to also include powerlifting, which means he wants to get really strong. Not everyone’s goals are exclusively about getting lean an healthy.

I agree and disagree with David below. Energy does mean for good performance in your workout but a ‘poor performance workout’ doesn’t exclude results. I’ve found that my deads, squat and bench all went up doing fasted workouts. My workouts would suck in the morning but every couple of weeks I would do an evening benchmark workout and find my 1RM. Even though my fasted lifting was sub par in the moment it resulted in huge gains when fed.

Mike wrote on April 25th, 2012

I have one meal a day four days a week (mostly because I enjoy eating my face off once a day), I’ve noticed both strength gains and strength losses during the years I’ve been doing this, and imo it’s not tied to how often you eat but to total caloric intake/outake.

If you are running a caloric deficit then it doesn’t matter how frequently you eat, gaining strength is going to be very tough.

Right now I’m trying to get leaner cause I’m running a lot, so naturally I’m losing strength … has nothing to do with how frequently I eat. If I was focusing on getting stronger I would try to consume an extra 500 calories with dinner.

Thanks. I need to lose quite a bit of body fat. I’m trying to walk a fine line between gaining strength for fitness and losing fat for health and appearance. I don’t want to do too much of one at the expense of the other.

The general consensus in the LG community is that LG is more suited to someone who has already gained strength on a program like Starting Strength or Strong Lifts and is now looking for body recomposition – i.e. dropping body fat levels to single figures.

My own experience has been that a program like Starting Strength is really tough on LG so I have decided to just focus on strength and worry about fat later.

Make the most of newb gains while you can. Don’t worry too much about body fat until you can deadlift 2x body weight, squat 1.5xBW and bench BW

That said, you will still lose some body fat even without following LG if you’re lifting heavy and adding weight to the bar every workout as well as generally eating primal (with a few extra potatoes and milk)

Let your body be the guide. If your lifts stall or you’re struggling to recover, add calories. If your lifts are fine but your pants are tighter around the waist drop some calories.

Hope that helps.
Grant

Grant wrote on April 17th, 2012

Leangains is for guys who want to look like Berkhan, like natural bodybuilders. If you just want to burn fat and get lean and stronger, follow Mark on this. His results are easily sustainable without much effort under any condition, while the results of a Leangains style training go away easily and quickly once you stop following the regime for a while for whatever reason.

einstein wrote on April 18th, 2012

Brian, if you can share your current lifting PRs (squat, dead, bench), it will help. You might be able to fast and restrict calories while still making strength gains. It really depends on your current level of strength.

I have found that it’s hard to “do it all” at once. I.e., pick one of the two goals – get strong, or get lean. That said, most of what Rippetoe posts will tell you that most folks over 20%, even if they are “eating for strength” can still lose body fat on the SS or an intermediate program – you’re going to burn off a lot of the calories you take in through lifting. It won’t get you down to single digit body fat, but you probably won’t stay above 25%, either.

A lot of it, IMHO, comes back to WHAT you’re eating for strength. If you are sticking to a paleo/primal based, clean protein an veggies, intake while lifting lots of heavy things, then you’ll drop weight. If you’re on whole milk, GOMAD (which Rippetoe recommends for skinny kids trying to bulk up and gain strength) then, yeah, losing fat is going to be a bit harder.

Brian, based on what you’ve wrote, I would suggest the Leangains. And, from what has been posted earlier – IF is kind of an “intermediate” step, to be taken after the paleo/primal way of eating is your new “norm.” I wouldn’t personally try IF with a person very new to primal/paleo.

Dave wrote on May 2nd, 2012

I feel that all my gains come from recovery from training hard and not the actual workout, per se. It took me a few weeks to get dialed in to train as hard as I was used to in an unfasted state but once I did the gains came.

Recovery is really key to making gains. Replenish protein and other micro nutrients and get plenty of rest (sleep).

I was following the fasted training protocol with 10 grams of BCAA pre-workout, Leangains style, because I was trying to make strength gains. My strength gains were steady with that, but they practically doubled after I ditched the BCAA pre-workout. Like 2% gains every week instead of 1%.

Personally, I can get extra rep on everything, past the progression that I’ve planned, training completely fasted. A rep is fairly big considering I work with my 4-8 RM.

Now, I train exclusively in the completely fasted state. I guess I’m that guy… It fit’s my schedule and I love it.

In my experience, the strength gains fasted come easier compared to fed training. Everyone is a little different though.

I also use a power lifting type program (and I guess that I’d qualify as one of those advanced lifters according to his classification) and I have been experimenting with ~16 hour fasts on my off days with no ill effects.. I’ve still been getting no new PR s and gaining muscle

I realize I’m replying to an old post, but for the sake of others who may have the same question… I have had strength gains on heavy deadlifts, squats, and weighted dips while doing Warrior diet and also while doing leangains style IF. And im talking about week after week gains, not just occasional gains.

Mark – Thanks for the whole series on IF it has been very informative. Personally, I follow Martin’s method. It’s just easier for me to stay in a routine plus once I got into it, my hunger did change. So even though I stick to it during the week, I find on the weekends I automatically stick to it without even thinking about it. Also, I much prefer to do my workouts in a fasted state. I’ve been sticking to this pretty well since the first of the the year and have managed to gain strength on my workouts and lose 14lbs of fat – I’m not overweight, just trying to get in better shape and this method seems to work even for a 43 year old female !!!

Thanks for sharing this Tammy. I’ve been really interested in giving it a go with so much good information from Mark, but then I read the info about Women and fasting and it left me undecided.
You’re posting has encouraged me to give it a go. Thanks.

Great post, and perfect timing! I’ve been trying a few of these methods for the past few weeks, and still deciding which I like most, but I have a question on the LeanGains method. On the lifting / higher-carb days, would you follow the 250g – 300g carb guideline that you discussed in your carb refeed post? At 3 times per week, it seems like it might be overdoing it a little, no? Would you just slightly emphasize carbs over fats, but stick to 150g max as recommended in the the PB? What are your thoughts on this?

I don’t know man, 300g sounds awfully high for 3 days a week. I think I’m going to start out at ~200g carbs (mix of sweet potatoes, LOTS of cruciferous veggies, and only a little sugar from frozen cherries and blueberries) and see how that works out for me. I also plan on following Marks / Martin’s advice on keeping fat low – under 50g on lifting days. I just started today, so I guess we’ll see what develops over the next few weeks/months. Any more advice on the topic from anyone is welcome though =)

i have been doing lean gains now for about a month, its been working well but i like the idea of it being 10/14 for women i am going to give that a go, although most of the time i am fasting 16 /8 anyway!

thanks for this i am going to experiment as i like the idea of ustilising the natural need for food as a fast and a way of loosing fat

After reading the first part of the why fast series I started fasting. I was doing a Brad Pilon style or alternate day type fast. Basically, on Sunday, Tuesday and Thursday I only eat supper. A normal sized supper not a big feast. This gives me around a 20 to 24 hour fast depending on when I ate supper the night before.

This has worked for me and I have lost 2 to 3 pounds each week since. Now, I have been having two coffees with cream during my fasting days adding up to probably 75 to 100 cals spread over the day during my fast.

I’m hoping even though I do that I still get some of the other benefits Mark has pointed out in his posts on the subject.

Thanks for the interesting series of post Mark and for inspiring me to give it a try.

Since switching to paleo, my kids (girls, 9 and 11) often skip breakfast and or lunch. It’s totally up to them. I just tell them to eat as much as they want if they’re hungry and not to eat if they are not hungry. When they say they’re not hungry I don’t make them eat.

Back when they ate a normal breakfast and lunch, they would want a snack as soon as they got home from school. Now they have more energy and spend a lot less time eating. No lack of calories as they can eat a 1 pound New York steak with butter on top plus veggies grilled in tallow for dinner.

I’ve noticed the same thing with my kids, ages 4 and 6. CW tells us that small children have small stomachs and “have” to eat every couple of hors, so like most kids in their preschool, they ate breakfast, then a snack, then lunch, then a snack (or two), then supper and another snack before bed. Cutting the grains and loading them up on more eggs and meat, they might not ask for breakfast until 3 or 4 hours after waking. Then lunch is closer to when they used to have an afternoon snack. Supper is later, too. Snacks are rarely even considered. And they are still as energetic as ever (or even more so), are sleeping better (finally!), and are in the 90th percentile for height and 50th for weight. They have grok-let six packs and muscular legs that I covet!

We certainly allow our kids to “self-feed” on the weekends and as best as possible during the week. They are 5 and 2 years old. They tell us when they are hungry and we offer food then. We also have bacon left on the counter and they grab what they want when they feel like it.

It’s worked well so far. It also means we don’t have battles at the dinner table about eating their food.

I started with cooking half a package at a time. None left. Then I started making the whole package. None left. Last time I made bacon, I cooked two full packages and STILL none was left when I went back to the kitchen. My husband and kids seem to think that wild scavengers will invade the house and take it or something, so they are sure not to even leave a bacon bit-sized scrap left!

Decaf Debi wrote on April 18th, 2012

My hat is off to you.

That is a great thing you are doing for your kids, probably less of hassle for you as well. Your going to have some very healthy kids.

I recently began IF’ing — usually 16 hours, but did a 24-hr. fast the other day and it was pretty good.

Questions:
1. I can’t shake the idea that I’m messing with my metabolism. I can’t eat huge meals so w/2 meals per day I worry my calories are too low. Thoughts? I don’t want to be fasting and also undereating.

2. How do I know I’m burning fat vs. protein, once my initial glycogen stores are used up? People talk of being “fat adapted,” but I can’t tolerate huge quantities of fat. (I don’t process it well; slow-emptying stomach.) Does my body go straight from burning sugar to fat, or sugar to protein? I couldn’t remember.

I think that depends on if you are keto adapted or not. If you are IF’ing in a keto adapted state, the rules do change and you should not be in danger of soliciting the starvation response. I have personally never tried IF’ing without being keto adapted.
Protein does not actually burn well as a fuel, so you will go, I believe, from burning sugar to having to convert proteins (and some fat) into sugar to burn, aka ‘gluconeogenesis’. Unless you can become keto (fat) adapted, your body will continue to burn the sugar that it makes. In the even that you are not taking in enough calories, your body can catabolize a significant amount of your stored protein in this way (aka, your muscles).

Your body does not automatically switch from burning sugar to burning fat… there is a period of time in which it makes the conversion. You will start producing ketones within days of lowering your carbs, however, this does not mean that you are keto adapted… keto adaptation can take weeks to occur. In some people it can take months. I believe it depends of your metabolic state.

Have you considered ways of optimizing your digestion so that your stomach empties as it should?

First, your diet should have shifted you over given enough time – no grain, low carbs to more fats, protein. That could take a month? I guess longer if you haven’t really gone into the optimal carb zone on the chart Mark publishes.

Second, upon doing a fast how do you feel? If you have a ‘Carb Flu’, wiffy, headaches – then you are not keyto adapted yet. No problem, because the fast will actually accelerate your switch to fat burning.

Personally the only discomfort I have during a IF or even 3 day fasts is cold hands; and even that goes away with some mild exercise.

RobG wrote on April 18th, 2012

Ruby,

There are tests for ketosis. Ketostix are a test strip you submerge in urine. If it comes out a purple colour then you have a reasonable amount of ketones in your system. These are not the best for accuracy, but typically you are only looking for a guide, rather than trying to work out the exact mmol.
The better test is your blood and you can get home test devices for this that will to a finger prick test. These are very accurate.
The other method you can use is simply based on what you have eaten over a period of time. If you have had less then 50g of carbs everyday for a number of weeks, it is highly likely that you are in ketosis… But not guaranteed of course. If you have had say 10g of carbs per day for the same period the odds are greater.

Travis Koger wrote on April 26th, 2012

Interesting; thanks for the replies. I take digestive enzymes with meals to help with stomach emptying, but sometimes I just think I do better on a moderate (vs. high) fat diet.

I haven’t been consistently “paleo” for very long, but I feel fine during fasts, so I’ve really no idea whether my body is using protein or fat for energy. Hm.

Okay… on “ketosis” – I ordered a version of ketostix online… actually, something that’s supposed to test for a bunch of stuff… so we’ll see.

I get a little frustrated when I see stuff like, “you just know.” No, you don’t just know. If you’ve never been in ketosis, how the heck would you know? “Carb Flu” is also a totally subjective thing. People who have been consuming allergenic type food their whole lives have been known feel instantly better when they quit wheat and dairy. So where is their “carb flu?” Most of us probably lived our pre-paleo version of life life in some version of “carb flu” by virtue of having crappy diets. “Carb flu” is as vague a description as saying, “you can feel ketosis.” I’d love some hard evidence on both of these states and if a urine or blood test is the only way to know for sure, then I can accept that.

As for people talking about how many grams of carbs you eat… this is crazy talk. Sure, Mark talks about staying under a certain number of grams per day, but come on. Do you have a scale that you weigh everything on? No! The whole point is NOT to have to weigh food or count calories (which cavewomen didn’t do!) Foods don’t come in neatly packaged macro-nutrients. The concept of macro-nutrients is so totally over-simplified. Foods are combinations of nutrients. Almonds contain carbs, fats and protein. So… if you toss a couple nuts on a salad, add some bell pepper and maybe something else that’s not a PURE protein or fat, how can you really know if you’re eating less than 50 grams? Sure, one could just eat eggs and steak all day for a month to guarantee ketosis, but I don’t think Mark, Robb Wolf or any other paleo advocate promote this eating lifestyle as it’s a) boring b) untenable in the social sphere and c) there’s lots to be gained from mixing up your diet.

And… the fact that protein converts via gluconeogenesis to glucose makes me wonder about the tenability of getting into ketosis on a “pure” protein and fat diet in the first place.

Give me evidence, or give me… cake? Right now, cake sounds really effing good. Oh, right I must be in carb flu.

I do sort of a combination between the LeanGains and and Warrior Diet. I work out in the afternoon, and usually go straight to cooking dinner. I eat slowly until I’m full, and if I get hungry again before bed, there’s usually some leftovers. The only time I drink coffee is before a workout, but I don’t do any of the BCAA or other pre-workout supplements.

I’m somewhere I suppose between the Eat Stop Eat style and the Warrior Diet. I fast currently two days of the week. Having my last meal sometime between 6-9pm and then not having anything until the same time except for usually a small snack at 4-5pm when I get home while cooking dinner.

I run (usually HIIT/Sprints) on the fasting days around 1-2pm in the afternoon.

I’d also say my main motivator at this point is weight loss rather than the other benefits.

Also as a former fat guy who could set his clock with his stomach there is something strangely empowering about being able to skip eating for a day without hunger pains.

I started IF about two years ago. I started with the WD method because it was the easiest and most natural for me. I loved the expressions on people’s faces when I had to explain to them my first meal of the day comes at sundown (no it’s not Ramadan and no I am not Muslim). In summertime here in MN that can come as late as 10p.

Now I just eat WHEN. I do Crossfit and sometimes I do it fasted and sometimes I eat a small portion of protein beforehand. It just depends on my energy levels that day. I also am experimenting with post workout fasting for up to 3 hours after training. No sweat. I feel great and it is nice not having to plan meals all the time.

The real benefit comes on those days when I am out and about all day long and have no need to stop and find calories. This bewilders most of my friends who cannot comprehend my “madness”.

Hi,
I am with you on the WHEN approach, my hubby and I employ it all the time, and it is working for him even though he isn’t completely with the program. After decades of the conventional approach, it’s so liberating to have such a disconnect with food. If my day is busy, I simply don’t waste time eating. If there is nothing that I can buy to eat, I simply don’t when I am traveling. There is no guilt, no problem, and it’s so easy. I do try and throw in a longer fast every week, but generally eat only 2 or 1 meal a day. After a huge period of no weightloss, I am finally slowly shifting some again.
Cheers

Would you still recommend fasting for someone trying to put mass ON (or at the least, not lose any kind of weight or body fat). I know fasting doesn’t necessarily mean less food, but if I wanted to fast solely for the disease fighting reasons, would you recommend it still? What are some ways to ensure no mass is lost? Also, does having say cream in your coffee in the morning negate any fasting benefits? Any opinions are welcomed!

Katie, read the LG’s website. As the name of the program is “LeanGains” you’ll see Martin’s recommendations for IF while retaining and even gaining mass. All it takes is a couple looks at his photos to realize he’s not losing mass. His basic premise is to eat a large post-workout meal and if you train in a fasted state to supplement with BCAA’s to help with protein synthesis.

While he doesn’t recommend a Primal diet, there’s nothing to preclude it if you don’t mind getting a few extra healthy carbs here and there.

As to your cream in coffee question – I’d say it’s not ideal, but if you use a small amount of heavy cream (say less than 20-30 cals worth) then it probably won’t have much affect.

After trying EatStopEat and Martin’s method, I’ve come to the same conclusion as Mark – mix and match, and do what works with your life. I’ve settled on skipping lunch, with a some 24 to 36 hr fasts mixed in and had good results. It broke my weight loss plateau and I feel a lot better than constantly being in a fed state. But, a word of warning … Do it for at least a week, because the first week is BRUTAL. I know it’s different for everyone, but it was really, really hard for the first week, then like switch, it turned out to easy, like second nature.
I also think you should not try IF if your diet is out of whack nutritionally. I’ve tried IF in both states and I think the hunger is different (worse) if you are nutritionally deprived.

Since switching from a high carb, whole grain, and low fat diet, I have frequently found myself accidentally in the middle of an “eat when I’m hungry” fast. It feels great and I don’t waste time eating meals I don’t need. However, because I am very active, I have recently been trying the leangains approach. It seems to work well and my workouts don’t suffer, but I tend to think about the fast too often. I don’t want to stress about eating an hour early once in a while, so I’ll probably stick to eating when I’m hungry.

I’ve loosely followed LG’s style, but have an erratic workout schedule so one day I might train fasted and the next not. This makes it a little more difficult to plan the post-workout meals, but I try to maintain an approximate 16/8 eating schedule, cutting off around 8 or 9 pm. Recently I purchased Eat Stop Eat, and have started incorporating 24 hour fasts once or twice a week, usually on my rest days (basically extending my 16 hour window to dinner). One thing I have done is taken Martin’s recommendation of BCAA’s prior to a fasted workout. He seems to have done his research and is adamant that the effect of BCAA’s pre-workout is crucial to protein synthesis and overweighs the effect of any negative effect to the fast.

A couple of things I’ve noticed: Many of our hunger pains are psychological and can be solved by drinking more water, coffee, etc. Once you’ve become accustomed to fasting, you’ll know when you are really hungry and hunger pains will usually subside pretty quickly. Calories still count – just like in a completely Primal diet, calories will always count, so don’t gorge after a long fast. This defeats the purpose. Don’t go into a fast unprepared – if you’ve binged on sugar, alcohol, lack of sleep, etc the day before, a 24 fast is probably not your best bet. I usually don’t have a problem skipping breakfast, but would eat normally from lunch on then start a fast the next day. Similarly, don’t workout in a fasted state after an unhealthy binge session the day before.

The great thing about IF to me is relatively easy fat loss while also not having to worry about so many meals. This saves time and money and frees you up for other things. I used to be one of those that ate a big breakfast each morning, brought enough food to work for 2-3 snacks plus lunch, and cooked dinner eat night. The only thing is I never was fully satisfied, and always felt “hungry.” Mostly this was because I was bored at work and couldn’t wait to have some more smoked almonds, or eat that big ass salad, but now I don’t have to worry about that. I pick a fasting period and stick with it usually. I don’t think at this point I could follow the WHEN method though, since I still get a lot of false hunger signals and would be eating all the time again. Now I can tell how hungry I really am because that same salad fills me up for hours after a 16 hour fast. Another huge bonus for IF for me is the ability to keep away from office sweets. Previously if I were eating throughout the day, I’d have a sweet because “just one won’t hurt” but then often I’d go on a binge. Now if I’m fasting, I don’t have the urge as much to cheat because psychologically I know I’m in the middle of a fast and don’t want to break it for some crappy donut or cupcake.

Ditto. You just described me exactly. My eating window is a bit earlier in the day than is typical (because I want to avoid snacking at work where I’m surrounded by food) but I have no problem going to bed hungry and not eating breakfast until about 11 in the morning, regardless of when I wake up. I’ve never had that sort of freedom from food. Was a constant grazer, and was never satisfied by anything; I was always thinking about the next thing I was going to put in my mouth. Not anymore! I haven’t tried any 24 hour fasts but I think I’m going to start throwing one in between the 16/8 days. Can’t wait to see what impact it has.

Ok…so I really like the idea of WHEN fasting (I pretty much do it already anyway). But sometimes I’m truly hungry fairly often, even when I think I shouldn’t be (like on lower activity days). Anyone have this issue? Should I just eat…or wait it out until I’m hungrier, considering that I’m not expending much energy? Anyone feel like they have some insight for me? Thanks!

I maintain a high appitite on my rest days because of the workout the day before. I have always been that way. I actually don’t eat as much on workout days because the workout kills my hunger, but the next day, look out. I think it takes time for some people to refuel the system after a good workout.

Also try to drink more water and get out and walk, that will take care of the hunger too.

I’m a fan of the Leangains protocol. I train 3 days a week (Squat/DL, Bench, Chins) generally in the morning around hour 10-12 of my fast – I then continue the fast to 16 hours. Ideally I’d be lifting closer to hour 16 but I work 7-4 and this is the best I can do without shifting my eating schedule to not include the standard dinner hour and I’m just not willing to do that for a few reasons.

Even so, I’ve had great success using Martin’s recommendations. I definitely consider myself to be someone trying to put some weight back on after losing much more than anticipated following a standard Primal/Paleo life for the past 8 months or so. Not a bad result, just a shock that there was that much fat and that little muscle. After going from 215 to 165 in those 8 months I’m now just over 170 after about 3 months using the Leangains guide for IF and training.

Tried the 24 hour fast a couple times. Didn’t mind it but prefer the 16/8 method much more. Found myself thinking too much about where I was at with the 24 hour method. In a good groove w/ 16/8 and have no intentions on changing it.

Yes I am, Mario. Whenever I train in the morning during the week I follow Martin’s early morning fasted training protocol pretty closely. Usually 10g ~5:30, another 10g around 7:30, final 10g around 9:30 and lunch @ 11:30.

Often I will have a workout on the weekend and I will wait to go in until I’m at 16 hours and will just do the 10g pre-workout, come home and eat.

I have been loosely following LG’s, also (typically 17/7, skipping breakfast). I love the fact that I don’t have to “worry” about eating breakfast & am no longer longing for snacks in between meals. It has also helped with staying away from “treats” at the office. And, once 7pm hits, I know that my fasting period has started, so this has helped with late night snacking.

I haven’t yet experimented with fasting. I typically eat breakfast/lunch/dinner and a late afternoon snack. This article reminded me that I’d like to increase the gap between dinner and breakfast – if I eat dinner a little earlier, I can come close to fasting, and might also be able to skip my pre-dinner snack.

I like the idea of eating when hungry (isn’t that the purpose of eating afterall? :p) – and it goes hand in hand with mindful eating. Especially on weekends, when I can eat whenever, I try to remember to only eat when I’m actually hungry, rather than just because the clock says it’s mealtime.

I did ADF for a year. But I’m trying something different now. Mondays, Wednesdays and Fridays I eat one meal a day. This is a gigantic salad at around 6pm. I don’t eat any animal protein with it (just nuts, seeds, etc.) and I drink my coffees black. The rest of the days (except sometimes Saturdays, depending) I eat three meals and two snacks. All the meals have animal protein (grass-fed beef, elk, wild salmon, really good eggs, etc.) and I put heavy cream in my coffee. This gives me a 24 hour fast 3 days a week (sometimes on Saturday, too) and I’m finding it really easy. I’m thinking it’s simulating the days Grok couldn’t find anything to hunt.

I have really enjoyed basically doing the Warrior Diet. I don’t eat anything all day, black coffee in the morning when I wake up. I work out around 3:30 or 4:00 and then its dinner and maybe a snack late night. But I have always wondered if I am doing it correct. Am I eating enough? When you say “feast”, what does that entail?
Example: Coffee yesterday morning, nothing all day. No workout, and then had a large bowl of steamed shrimp and broccoli. Not a struggle to do but want to make sure that I am not hurting myself or setting myself up. Thanks for any help and support.

I eat pretty much the same way (Warrior Diet) with the exception that I have daily my cup of coffee with extra cream in the morning before my workouts. I work out in the mornings (kettlebells and rowing) and I don’t eat till dinner. Been doing this since January and it has become like second nature.

I’ve never really “feasted” as I’m just never really that hungry even with daily fasting. In addition, there is only so much meat and vegetables I can eat at one sitting, and I eat till I’m full. I feel extremely good so far, so whether I’m eating enough or not doesn’t make much of a difference to me. I’ve found something that is easy for me to do and and sustainable with the added benefit that I feel great everyday.

Not so much if you live in New England and work in an office. Even mid-day mid-summer, the angle of the sun isn’t great for getting your Vitamin D. And the sun’s too low in the mornings and evenings, when I’m out in the world during the week, to do me much good in terms of Vitamin D.

merryish wrote on April 18th, 2012

Most vitamins & supps suggest to take with food, so I wait until a meal (I IF @17 hrs daily)

I go with WHEN, because I am already naturally thin and worry about losing weight, so I eat when I am hungry. Even still, I typically go about 12 hours a day without eating, and every Saturday I don’t eat my first meal until around 2:30, 3 or sometimes 4 in the afternoon because I am usually not hungry before then.

I tried to fast for 24hrs in January after going through a food overhaul during the holidays. I did it Eat Stop Eat style after a friend of mine recommended it. I was in a haze, couldn’t focus, felt sick and only made it to 22 hrs.
After Mark’s IF series, I decided to try again since I’ve been eating Primal for about a month now. I have to say it was SO MUCH easier. I did not feel any effects of the fast and felt that I could go on longer.

Mark,
Thanks so much for this summary, perfect timing actually! I’ve been reading up on fasting methods since you first introduced the “Why Fast” series. I found that 16/8 is the most natural fasting period because I’m not really a breakfast kind of girl. However, I’m not eating a feast for dinner as described in Leangains because I can eat that must after working out and I’m not interested in becoming too muscular, just lean and toned.

I have been using Berkhans form of fasting since Jan 2. All i can say is i am blown away by the results. I have lost 35lbs, and i can confidently say it is almost purely bodyfat as my strength has gone up immensely. My deadlift went from 245lbs for 6 reps to 405lbs for 6 reps. Bench, squats and chins have all increased by quite a significant margin as well. Im sold, i will eat this way for the rest of my life. It really has changed my life.

Congrats on the results man! Good for you! Hey so, earlier in the comments section of this post, I asked a question about grams of carb consumption on lifting days. Do you follow Mark’s refeed recommendations of 250-300g? Do you follow something else? Are you doing the LG approach within the Primal guidelines?

I’ve started combining Alternate Day Fasting with the “Warrior Diet” eat once a day thing in a limited window. For one day I don’t eat (I might have heavy cream with my coffee and about 8oz of plain kefir or yogurt mixed with cream in the afternoon if I’m feeling really hungry but no solid food). The next day I only eat within a 6 hour window.

The nice thing about only eating once a day is I don’t really have to count carbs as carefully. I still avoid grains, sugar, potatos etc, but it gives me a little more wiggle room.

I can’t really do the eat when I’m hungry thing because if it was up to me I’d eat like 6 times a day. I have been Paleo for over a year and even with working out I have not been able to drop more than about 10 pounds. I started using IF to break that plateau and dropped 5 lbs in the first week. I have already dropped from 225 to 165 in the past 2 years! This last 30 lbs has got to be the most stubborn!!!!!

Good results and feel awesome on this schedule: 2pm-8pm eat; coffee with coconut oil and grass fed butter on rising about 6am ish. 24 hour fast on Monday from Sunday dinner to Monday dinner and a “normal” Saturday to not stress out the kids!

Great series Mark! It has inspired me to jump into the realm of intermittent fasting. I’ve taken to the 24 hour fast. Eat a normal meal for dinner (by 8:00 Pm) then not again for 24 hours. Suprising how easy this is now that I have switched to Primal. I used to be a total carbaholic, couldn’t go more than 2-3 hours without eating something or I’d go hyper-glycemic.
Thanks for all the information on your site, it’s really helped me to remain focused and committed.

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